Method of manufacturing semiconductor device

Abstract

The method of manufacturing the semiconductor device includes nitridizing a silicon substrate with ammonia while heating the silicon substrate, then heating the silicon substrate in an atmosphere containing nitrogen and oxygen to form a gate insulating film including a silicon-based insulating film containing nitrogen and oxygen, then annealing the silicon substrate in an oxygen atmosphere, and forming a gate electrode on the gate insulating film.

1 . A method of manufacturing a semiconductor device comprising:
 nitridizing a silicon substrate with ammonia while heating the silicon substrate;   then heating the silicon substrate in an atmosphere containing nitrogen and oxygen to form a gate insulating film including a silicon-based insulating film containing nitrogen and oxygen;   then annealing the silicon substrate in an oxygen atmosphere; and   forming a gate electrode on the gate insulating film.   
     
     
         2 . The method of manufacturing a semiconductor device according to  claim 1 , wherein
 the nitridation with ammonia is made at a temperature of 500° C.-900° C.   
     
     
         3 . The method of manufacturing a semiconductor device according to  claim 1 , wherein
 the atmosphere containing nitrogen and oxygen is a N 2 O atmosphere.   
     
     
         4 . The method of manufacturing a semiconductor device according to  claim 1 , wherein
 a temperature of the atmosphere containing nitrogen and oxygen is 800° C.-1000° C.   
     
     
         5 . The method of manufacturing a semiconductor device according to  claim 1 , wherein
 a temperature of the oxygen atmosphere is 400° C.-850° C.   
     
     
         6 . The method of manufacturing a semiconductor device according to  claim 1 , wherein
 an oxygen partial pressure of the oxygen atmosphere is 0.03 Torr-90 Torr.   
     
     
         7 . The method of manufacturing a semiconductor device according to  claim 1 , further comprising, before nitridizing the silicon substrate with ammonia,
 forming a silicon oxide film on the silicon substrate.   
     
     
         8 . The method of manufacturing a semiconductor device according to  claim 7 , wherein
 forming the silicon oxide film on the silicon substrate is made at a temperature of 850° C.-950° C.   
     
     
         9 . A method of manufacturing a semiconductor device comprising:
 nitridizing a silicon substrate with ammonia while heating the silicon substrate;   then annealing the silicon substrate in an oxygen atmosphere;   then heating the silicon substrate in an atmosphere containing nitrogen and oxygen to form a gate insulating film including a silicon-based insulating film containing nitrogen and oxygen; and   forming a gate electrode on the gate insulating film.   
     
     
         10 . The method of manufacturing a semiconductor device according to  claim 9 , wherein
 the nitridation with ammonia is made at a temperature of 500° C.-900° C.   
     
     
         11 . The method of manufacturing a semiconductor device according to  claim 9 , wherein
 the atmosphere containing nitrogen and oxygen is a N 2 O atmosphere.   
     
     
         12 . The method of manufacturing a semiconductor device according to  claim 9 , wherein
 a temperature of the atmosphere containing nitrogen and oxygen is 800° C.-1000° C.   
     
     
         13 . The method of manufacturing a semiconductor device according to  claim 9 , wherein
 a temperature of the oxygen atmosphere is 400° C.-850° C.   
     
     
         14 . The method of manufacturing a semiconductor device according to  claim 9 , wherein
 an oxygen partial pressure of the oxygen atmosphere is 0.03 Torr-90 Torr.   
     
     
         15 . The method of manufacturing a semiconductor device according to  claim 9 , further comprising, before nitridizing the silicon substrate with ammonia,
 forming a silicon oxide film on the silicon substrate.   
     
     
         16 . The method of manufacturing a semiconductor device according to  claim 15 , wherein
 forming the silicon oxide film on the silicon substrate is made at a temperature of 850° C.-950° C.   
     
     
         17 . A method of manufacturing a semiconductor device comprising:
 forming a silicon oxide film over a silicon substrate;   forming a silicon nitride film over the silicon oxide film;   then annealing the silicon substrate in an oxygen atmosphere to form a gate insulating film including a silicon-based insulating film containing nitrogen and oxygen; and   forming a gate electrode on the gate insulating film,   annealing the silicon substrate being made at a temperature of 400° C.-850° C. in an atmosphere of a 0.03 Torr-90 Torr oxygen partial pressure.   
     
     
         18 . The method of manufacturing a semiconductor device according to  claim 17 , further comprising, after forming the silicon nitride film and before forming the gate insulating film,
 making a thermal processing in an atmosphere containing nitrogen or oxygen.   
     
     
         19 . The method of manufacturing a semiconductor device according to  claim 17 , wherein
 in forming the silicon nitride film, the silicon nitride film is formed by using NH 3  and Si 2 H 4  or SiH 2 Cl 2  as a raw material gas.